Aastra Dialog Option Unit for 4222 4223 4224 4225 & 4425

£35.00 ex. VAT

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Product code: DBY420 01/1 R3A – Aastra Dialog Option Unit for 4222 4223 4224 4225 & 4425 is in stock.

The Aastra Dialog Option Unit (DBY420 01/1 R3A) allows connection to the Dialog 4222, 4223, 4224, 4225 or 4425 phones of either:-

Extra Bell

Busy Signal*

Combined Extra Bell and Busy signal*

*Busy signal function is not appicable for Dialog 4224 Operator connected to MD110

Office Phone Shop stock a wide range of Aastra business phones.

The Aastra Dialog Option Unit (DBY420 01/1 R3A) is available new and boxed complete with a full warranty.

When contacting us about this product please quote Aastra Dialog Option Unit or DBY420 01/1 R3A.

Additional information



At Office Phone Shop we offer a full one year warranty* on all new, remanufactured and refurbished products.

We offer after sales support** and advice from answering simple user questions to full system programming services. These services are maintained through a combination of online support documents and a full range of business telecoms services, including our maintenance and support services.

We will do all we can to offer our assistance with any problems you may encounter.

Office Phone Shop has built its reputation on offering customer satisfaction. So if you are a customer with a problem, we want to know about it. Our details can be found on the contact page.

*some DECT telephones & untested equipment has a reduced time period warranty.

**where relevant to products/services offered.

UK Delivery

We aim for next day delivery. Any order placed before 1.00 pm on any business day (Monday – Friday excluding Bank Holidays) should be delivered the next business day before 5.30 pm (assuming the item is in stock).

Worldwide Delivery

We ship worldwide from our UK warehouse.

Read more information on Delivery.

  1. The Customer is required to inspect all goods upon receipt and to notify Office Phone Shop of any defects or complaints within 7 days of receiving goods.
  2. It is the responsibility of the customer to ensure the safe return of faulty or incorrect goods to Office Phone Shop.
  3. All goods returned must clearly state customers name, order no, telephone number, fault details and proof of purchasing. These goods must be in Office Phone Shop’s original packaging and condition, with original insertions, fixtures and parts. Failure to do so will result in the refund being invalidated.
  4. We use tamper proof labels which are stuck to each item sold by Office Phone Shop. This ensures that goods have been purchased from Office Phone Shop. When the label is peeled back Office Phone Shop Company details sticks to the glue and the label will then say void. No goods will be accepted back unless this label in intact.